CLASS

In ESO you can heal on any Class, and each class offers something to a healer with unique class skill set. The meta healer is generally not based on who heals the strongest but is based around what the group needs to optimize group buffs and debuffs.

If you are only building one healer, then I recommend you choose based on the class you will enjoy playing and/or ease of play, but remember all classes are viable.

Templars and Wardens are the two easiest and strongest healers, in my opinion. These classes complement each other well, and commonly one or both are used in trial groups.

Templar

Warden

TEMPLAR

Templars are strong healers, with a robust healing toolkit and target debuffs. Templars have early access to shards, which assist groups with resource management, and also offer debuffs, synergies, and cleansing spells.

Import class skills to unlock:

Rushed Ceremony; morph to Breath of life – Restoring Light skill line
A very powerful self-heal that heals you and another person really well in a pinch.
Cleansing Ritual; morph to Extended Ritual – Restoring Light skill line
A huge ground heal that lasts for 24 seconds and offers a reliable synergy that cleanses up to 5 negative effects from a player who activities the synergy.
Spear Shards; morph to Luminous Shards – Aedric Spear skill line
Offers a synergy that quickly restores a teammate's primary resources. Can be cast a good distance, and also does decent damage.

Other useful skills

Rune Focus; morph to Channeled focus – Restoring Light skill line
When cast, this spell increases your resistances by 5280. Standing within the rune also increases your resistances by a further 50% and restores 240 magicka per second. Great where you can stand still and need to be able to absorb some damage.
Restoring Aura; morph to Radiant Aura – Restoring Light skill line
Applies an AOE magicka steal, restoring 168 magicka per second to all allies when damaging the target the buff is applied to, and increases your magicka, health, and stamina recovery by 20% while slotted. Only used over Elemental Drain when Major Breach is being applied to the target from another source - i.e. a tank is running Pierce Armor.
Sun Fire; morph to Vampire's Bane – Dawn's Wrath skill line
This is a damage skill that lasts 14 seconds and provides major prophecy to you increasing your critical rating by 2629. Used to maintain the Illuminate and Prism passives which grant Minor Sorcery and ultimate generation to the group. Only used if there is not another Templar in a group to maintain this buff or while wearing Z'en's Redress set.
Backlash; morph to Power of the light – Dawn's Wrath skill line
Applies Minor Breach, reducing the target's spell and physical resistance. Also used to maintain the Illuminate and Prism passives which grant Minor Sorcery and ultimate generation to the group. This is used less often now that Minor Breach can also be applied by the taunt skill Pierce Armor. Generally only used when tanks are not able to apply Minor Breach, such as in Sunspire, when the main tank is using a ranged taunt. Should be maintained at all times when needed.
Nova; morph to Solar Prison – Dawn's Wrath Skill line
Applies Major Maim to the target reducing their damage done. Provides a synergy dealing additional damage and stunning enemies in the area. Generally used more in four-man content and while leveling. The other morph is also useful, but the extra damage of this morph makes it the preferred option.

Passives:

I recommend all of them, but some you need to be more actively aware of to ensure you are activating them regularly. Others are less important, as they offer marginal improvements. I will discuss the ones that have to be activated and how they are procced, and list the unimportant ones in case you are short on skill points. Though, as above, I recommend you get all class passives, since they generally have some benefit to you.

Must haves:

Illuminate (Dawn's Wrath) – Casting of a Dawn's Wrath ability (ex. Vampire's Pane, Power of the Light, Solar Prison) grants Minor Sorcery to you and your group for 20 seconds, increasing your spell damage by 10%. This is a must if you are the only Templar in the group, as it is your job to maintain this buff at all times. This is easy to maintain with skills in the line having long durations.
Prism (Dawn's Wrath) – Casting a Dawn's Wrath ability generates 3 ultimate. The effect can occur every 6 seconds. Extra ultimate generation for you to increase War Horn uptime while maintaining the Minor Sorcery group buff.
Restoring Spirt (Dawn's Wrath) – Reduces the health, magicka, stamina and ultimate cost of all of your abilities. Reduces the cost of every skill, and thus increases your sustain.
Mending (Restoring Light) – Increases the healing effects of all Restoring Light abilities by up to 12% depending on the severity of the target's wounds. Increases the effectiveness of class heals.

Light Weaver (Restoring Light) – Provides a bonus to Restoring Light abilities, increasing the duration of your Aura by 20%. Healing Ritual grants 2 ultimate to allies healed under 60% health and grants 16500 resistances while channeling Rite of Passage. Increases team ultimate generation.

Sacred Ground (Restoring Light) – While standing in, and for up to 4 seconds after leaving your own Cleansing Ritual, Rune Focus, or Rite of Passage you gain Minor Mending, increasing your healing done by 8% and increasing the amount of damage you can block by 10%. Grants you extra healing power and migration for free.

Less important:

Burning Light (Aedric Spear) – Increases damage done when you cast an Aedric Spear ability 4 times in rapid succession. Unless you are running Puncturing Strikes as a damage ability you are not going to get the benefit of this passive.
Enduring rays (Dawn's Wrath) – While the extra duration is nice on Vampire's Bane and Solar Prison, it's not essential.

Skill Bars

Standard - with a Master's Restoration Staff on the front bar:

These skills are what I recommend you use when, as the healer, you do not need to provide Minor Breach with Power of the Light, but are still responsible for maintaining Minor Sorcery uptime. Radiant Aura is on the front bar, because having it slotted increases health, stamina, and magicka recovery. Reviving Barrier is on the front bar rather than the back for the extra passive magicka recovery in the support skill line.

Front

Breath of Life / Illustrious Healing / Combat Prayer / Energy Orb / Flex: Radiant Aura or Radiating Regeneration, Bone Surge or Efficient Purge with Reviving Barrier.

Back

Elemental Blockade / Extended Ritual / Flex: Vampire's Bane or Elemental Drain / Luminous Shards / (Flex) Channeled Focus, Circle of Preservation or Overflowing Altar with Aggressive Horn.

With Power of the Light - with a Master's Restoration Staff on the front bar:

Front

Breath of Life / Illustrious Healing / Combat Prayer / Energy Orb / Flex: Power of the light with Reviving Barrier.

Back

Elemental Blockade/ Extended Ritual / Flex: Radiant Aura, Elemental Drain, Bone Surge, or Efficient Purge / Luminous Shards / (Flex) Channeled Focus, Circle of Preservation, or Overflowing Altar with Aggressive Horn.

Wearing Z'en's Redress - with a Master's Restoration Staff with a Flame enchant on the front bar and an Zen's inferno staff back bar with a Poison enchant:

To obtain the maximum 5% increased damage using the Z'en's Redress set you need to be able to apply 5 different DoTs to the target. The DoTs applied here are Burning, via Flame enchant, from light attacks (4 seconds), Poison, via Poison enchant, on your light attacks (6 seconds), Soul Splitting Trap (10 seconds) magicka DoT, Vampire's Bane magicka DoT (14 seconds) and Lightweight Breast trap DoT (10 seconds), with the shortest duration DoTs are on the front bar.

Front

Breath of Life / Illustrious Healing / Combat Prayer / Energy Orb / Soul Splitting Trap with Reviving Barrier.

Back

Elemental Blockade / Extended Ritual / Vampire's Bane / Luminous Shards / Lightweight Beast Trap, Scalding Rune or Degeneration with Aggressive Horn.

I like Lightweight Brest trap as As Z'en's is commonly worn with Martial Knowledge having a skill that costs stamina assists you with your stamina management while providing a DOT that can be applied from range. I prefer Scalding rune over entropy for the extra 2 second duration, but Degeneration gives you major sorcery and in combination with Vampires Bane that gives you major prophecy enabling you to use different pots such as heroism pots for extra ultimate generation.

Skills

Passives

Bars

Anchor illuminate

templar Skills

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Templar

Sunfire

warden

WARDEN

Wardens offer buffs, debuffs, and have great sustain. Their class skills and passives offer many buffs and debuffs that would otherwise need to be applied using five-piece sets, which allows groups to use other sets to increase DPS and group survivability. Because of this, a Warden healer is generally a must-have in trial groups. With the changes to the ice staff in the Markarth DLC, and the introduction of Minor Brittle buff when applying chilled status effect when holding an ice staff, Warden healer popularity increased again, to the point that they are the first healer picked in most trial groups.

Import Class Skills to Unlock

Healing seed; morph to Budding seeds – Green Balance skill line
This ability summons a field of flowers that has an 8m radius. All allies within the field heal for 137 every second, and when it blooms it triggers a 1234 heal. A synergy within the field can be activated by an ally, or by you, by activating the ability again to instantly trigger the bloom, healing for 1188 health over 5 seconds. A weak heal over time with a strong burst heal, this heal offers a reliable synergy for tanks running Alkosh, and this ability's heal procs the Maturation, Accelerated Growth, and Nature's Gift passives.

The Corrupting Pollen morph is also commonly used, which means that the healer does not reactivate the skill to activate the bloom, but you lose the small HoT and gain a Major Defile debuff, reducing enemies healing received by 30%. This morph is not really used for the Defile, but for the instant recast of the ability once the synergy is taken to provide more synergies to the group.

Which morph you use will depend on your group and build.
Frost Cloak; morph to Expansive cloak – Winters Embrace skill line
Gives Major Resolve to all allies within 28m radius, increasing physical and spell resistance by 5280 for 20 seconds. The huge radius and long duration of the skill mean the whole team can now be provided with increased resistances, improving group survivability.

Ice Fortress is the other morph, which only has an 8m radius but increases the duration, and provides you Minor Protection, reducing your damage taken. This morph can be used if your team is hard stacked and will increase your survivability, which is the first priority, so use this morph if you need to, but if you can survive without the extra personal damage mitigation go for the other morph, which almost always buffs the whole group.
Swarm; morph to Fetcher Infection – Animal Companions skill line
Applies Minor Vulnerability to the target, increasing the target's damage by 5% for 10 seconds and dealing 1266 magic damage. As a healer, we are using this skill for the 5% increased damage taken debuff. Reapply on cooldown to keep this buff up 100% of the time. You can use the Growing Swam morph, which changes this ability to a stamina ability, to help reduce your stamina pool to less than 50% when using a set like Martial Knowledge.
Betty Netch; morph to Blue Betty – Animal Companions skill line
This skill restores 4416 magicka to you over 25 seconds, removes 1 negative effect every 5 seconds, and grants you Major Sorcery - increasing your spell damage by 20%. This is a self-buff skill that increases your healing power, magicka recovery, and survivability. I would recommend having it on the back bar, with Fetcher flies on the front, to take advantage of the Flourish passive, increasing your magicka and stamina recovery by 12%.

Other Useful Skills

Secluded Grove; morph to Healing Thicket – Green Balance skill line
A very useful ultimate ability that instantly heals the most injured ally for 987 health, and continues to heal you and your allies in the area for 331 health every second for 6 seconds, and will also continue to heal you or allies after leaving the area for 4 seconds. A very strong heal that continues even when allies have to leave the area to avoid mechanics. And at only 90 ultimate, which is less than half a War Horn, it can be a great pinch heal.
Fungal Growth; morph into Enchanted growth – Green Balance skill line
A narrow 20m cone AoE in front of you that heals all targets for 822 health. Any target healed gains Minor Intellect and Endurance, increasing their magicka and stamina recovery by 20% for 20 seconds. A strong heal that provides increased resources to all healed, and the ability's heal procs the Maturation, Accelerated Growth, and Nature's Gift passives. Used when the team is going to be hard stacked, and in general is one of my flex spot options.
Nature's Grasp; morph to Bursting Vines – Green Balance skill line
You launch yourself at the target healing them for 1233 instantly, and if you are in combat and the target is under 60% health you gain 10 ultimate. This effect can occur every 4 seconds. A situationally useful skill that is used when you know an individual ally will need a massive heal, I love it when healing ice cages in vet Sunspire. With a strong heal that gets you to the target super quick, and ultimate generation, you can not go wrong with the heal in that situation. Otherwise, the skill's use is quite limited.
Impaling Shards; morph to Winter's Revenge – Winters Embrace skill line
Summons icy shards in an area, dealing Frost damage and reducing movement speed by 30% for 3 seconds to all targets affected. Damage of this morph is based on your max magicka and has a higher chance to apply the Chilled status effect. Used in ice staff builds to increase the chance of applying Chilled and Minor Brittle with chance multiplicative with the Glacial Presence passive.
Sleet Storm; morph to Permafrost – Winters Embrace skill line
Creates a 10m storm around you, dealing Frost damage. Applies the Chilled status effect and decreases movement speed by 70% to all enemies hit. Also provides Major Protection to all allies within, reducing their damage by 10%. Used in ice staff builds to guaranteeing Chilled and Brittle effects are applied to targets within area of effect, but it is a high cost ultimate at 200.

Passives:

I recommend all of them but some you need to be more actively aware of to ensure you are activating them regularly and others are less important as they offer marginal improvements. I will discuss the one that have to be activated one and how they are procced and list the unimportant ones in case you are short on skill points, but as above, I recommend you get all class passives, as they generally have some benefit to you.

Must haves:

Maturation (Green Balance) – When you heal yourself or an ally, grant Minor Toughness for 20 seconds, increasing their max health by 10%. Increased survivability for you and your whole team.
Accelerated Growth (Green Balance) – When you heal a target under 40% health with a Green Balance ability, gain Major Mending, increasing your healing done by 16%. Increases your healing done to all allies.
Nature's gift (Green Balance)- When you heal an ally with a Green Balance ability, restore 250 Magicka or stamina, whichever is lower. Free resource recovery.
Flourish (Animal Companions) – Increases magicka and stamina recovery by 12% when an Animal Companion ability is slotted. Free resource recovery.
Bond with Nature (Animal Companions) – Restore 1260 health when your Animal Companion ability ends (dies or unsummoned). Increased survivability.
Savage Beast (Animal Companions) – When you cast an Animal Companion ability while in combat, generate 4 ultimate. Increased ultimate generation means better War Horn uptime.
Glacial Presence (Winter's Embrace) – Increase your chance of applying Chilled status by 200% with a Winter's Embrace skill. Only needed if running an ice staff build and you have a Winter's Embrace skill slotted on an ice staff bar, which will increase the chance of applying Minor Brittle, which increases the target's critical damage taken by 10%.
Icy Aura (Winter's Embrace) – Reduces the effectiveness of snares applied to you by 15%. Must have in PvP, and nice to have in PvE.

Less important:

Advanced species (Animal Companions) – Increases your damage done by 2% for each Animal Companion ability slotted. Will increase your DPS slightly but will have no effect on the strength of your heals. You can live without this passive.
Piercing cold (Winter's Embrace) – Increase frost damage by 10%. Will increase your DPS slightly but will have no effect on the strength of your heals. You can live without this passive

Skill Bars

Bold skills are recommended

Standard – with a Master's Restoration Staff on the front bar:

Front

Fletcher Infection / Illustrious Healing / Combat Prayer / Energy Orb / Flex: Expansive Frost Cloak or Radiating Regeneration or Efficient Purge with Reviving Barrier or Healing Thicket

Back

Elemental Blockade/ Budding Seeds / Flex: Elemental Drain / Flex: Overflowing Alter or Expansive Frost Cloak / Blue Betty with Aggressive Horn

Frost variation – with a Vateshran's Frost Staff on the back bar. The principle behind this set up is to maintain Brittle uptime by using frost ultimates.

Front

Fletcher Infection / Budding Seeds / Enchanted Growth / Energy Orb / (Flex) Expansive Frost Cloak or Efficient Purge with Reviving Barrier or Ice Comet

Back

Elemental Blockade / Winter's Revenge / Elemental Drain / (Flex) Overflowing Altar or Expansive Frost Cloak / Blue Betty with Permafrost or Aggressive Horn

Stamina variation – with Restoration Staff front and Bow back bar, and the stamina sets in the build section.

Front

Growing Swarm / Budding Seeds / Combat Prayer / Energy Orb / (Flex) Expansive Frost Cloak or Razor Caltrops, Radiating Regeneration or Illustrious Healing with Healing Thicket or Reviving Barrier

Back

(Flex) Venom Arrow or Arrow Barrage / Soothing Spores or Circle or Preservation / Echoing Vigor / Razor Caltrops / Bull Netch with Aggressive Horn

PVP

Front: - Restoration staff

Illustrious Healing /Radiating Regeneration / Race Against time / Deceptive Predator / Expansive Frost Cloak / with Reviving Barrier / Life Giver

Back: Ice Staff or Sword and Shield

Living Trellis / Budding Seeds / Echoing Vigor or Energy Orb or Overflowing Altar /Deceptive Predator/ * Growing Swarm or Fletcher Infection or **Blue Betty with Healing Thicket / Reviving Barrier

*With the hybrid set ups realy does not matter which morph both are strong and apply minor vulnerability de-buff so its about your build and play style I find having 1 or 2 stamina abilities helps with sustain without reducing healing potential.

**Blue Betty is great but consider if you want a purge every 5 seconds in PvP with Plague Breaker out there at the moment it can be dangerous.